President barak obama issued two documents related to critical infrastructure that increase the national focus on issues of security and resilience. these two
documents are:
select one or more:
a. presidential policy directive-21: critical infrastructure security and resilience.
b. presidential policy directive-2: implementation of the national strategy for countering biological threats.
c. executive order 13636: improving critical infrastructure cybersecurity.
o d. executive order 13616: accelerating broadband infrastructure deployment.